The S&P 500's Biggest Movers on the Week

Are these poppers and droppers in your portfolio?

The S&P 500 finished last week lower, slipping 1.2% to 1,016.4; while the index climbed a healthy 3.4% for the month of August. However, the index kicked off September with a rocky start, pulling back for the first couple of days of the month.

Pops and dropsHere are the five biggest S&P 500 pops and five biggest S&P 500 drops of last week (measured Friday close to Friday close):

Winners on the week:

Company

Percentage Gainon the Week

Newmont Mining(NYSE:NEM)

12%

Textron

9%

Motorola(NYSE:MOT)

7%

Costco Wholesale(NASDAQ:COST)

7%

BJ Services(NYSE:BJS)

7%

Source: Capital IQ (a division of Standard & Poor's).

Losers on the week:

Company

Percentage Losson the Week

AIG(NYSE:AIG)

(20%)

McGraw-Hill

(13%)

SunTrust Banks

(12%)

Moody’s(NYSE:MCO)

(11%)

Gannett(NYSE:GCI)

(11%)

Source: Capital IQ (a division of Standard & Poor's).

A look at some of the moversShares of Moody's and McGraw-Hill, owner of Standard & Poor's, slumped last week after a judge permitted a case brought against the credit rating agencies to proceed. The judge ruled that freedom of speech protections don't necessarily apply to ratings disseminated to a limited group of investors.

Baker Hughes acquired oilfield services company BJ Services last week in a cash and stock deal valued at $5.5 billion. The oil and gas equipment company's purchase will better enable it to compete with larger players in the oil services area, like Schlumberger and Halliburton.